Contact Energy is expecting to see the level of Lake Hāwea increase for summer, a spokesperson told the Wānaka App.

Contact operates the Hāwea dam and control structure which regulates the flow out of and the level of Lake Hāwea. 

Lake Hawea is the only significant controlled hydro storage facility on the Clutha Mata Au River, providing water on an ‘on demand’ basis.

“Following recent rainfall, Lake Hāwea is back at normal levels for this time of year,” a Contact spokesperson said.

“Our teams are currently dealing with high flows and operating within consent conditions and regional flood rules.

“Typically, we see lower electricity demand following winter, so we expect to reduce releases from the lakes from now into the spring and summer months.”

Guardian of Lake Hāwea Don Robertson said Transpower had requested withdrawing water from hydro lakes in August, which in some cases would have reduced them below their low operating levels. 

A Transpower request to Contact Energy in early August would have reduced Hāwea’s lake level to two metres below its low operating level (338 metres above sea level/masl) if it had been implemented, Don said.

“These requests were in response to low rainfall (low hydro lake levels), less wind than normal and reduction in gas availability for thermal power generation, all contributing to a potential drop in generation capability with concerns about the risk of likely widespread power cuts,” Don said.

When the lake gets below a certain level concerns are raised about the risk of windblown silt from the exposed lake bed affecting lakeshore dwellings. 

Lake bed exposure below 338masl also has the potential to cause widespread mortality of submerged lake plants, aquatic invertebrates and possibly some fish, Don said.

“Fortunately the lake level has risen steadily since mid-August,” he said.

On Wednesday afternoon Lake Hāwea was at 341.018masl and rising, according to Otago Regional Council monitoring.

PHOTO: Wānaka App